Files
game-physics/AntTweakBar/examples/TwSimpleSFML.cpp
2017-10-11 15:01:05 +02:00

250 lines
9.0 KiB
C++

// ---------------------------------------------------------------------------
//
// @file TwSimpleSFML.cpp
// @brief A simple example that uses AntTweakBar with OpenGL and SFML.
// This example draws moving cubic particles with some
// interactive control on particles generation.
//
// AntTweakBar: http://anttweakbar.sourceforge.net/doc
// OpenGL: http://www.opengl.org
// SFML: http://www.sfml-dev.org
//
// @author Philippe Decaudin
//
// ---------------------------------------------------------------------------
#include <AntTweakBar.h>
#if defined(_WIN32)
// MiniSFML16.h is provided to avoid the need of having SFML installed to
// recompile this example. Do not use it in your own programs, better
// install and use the actual SFML library SDK.
# define USE_MINI_SFML
#endif
#ifdef USE_MINI_SFML
# include "../src/MiniSFML16.h"
#else
# include <SFML/Graphics.hpp>
#endif
#if defined(_WIN32)
# include <windows.h> // required by gl.h
#endif
#include <GL/gl.h>
#include <GL/glu.h>
#include <list>
#include <cstdlib>
#include <cmath>
// Pseudo-random value between -1 and 1
float Random()
{
return 2.0f * ((float)rand() / RAND_MAX) - 1.0f;
}
// Particle randomly initialized
struct Particle
{
float Size;
float Position[3]; // [px, py, pz]
float Speed[3]; // [vx, vy, vz]
float RotationAxis[3]; // [rx, ry, rz]
float RotationAngle; // in degree
float RotationSpeed;
float Color[3]; // [r, g, b]
float Age;
Particle(float size, float speedDir[3], float speedNorm, float color[3]) // Constructor
{
Size = size * (1.0f + 0.2f * Random());
Position[0] = Position[1] = Position[2] = 0;
Speed[0] = speedNorm * (speedDir[0] + 0.1f * Random());
Speed[1] = speedNorm * (speedDir[1] + 0.1f * Random());
Speed[2] = speedNorm * (speedDir[2] + 0.1f * Random());
RotationAxis[0] = Random();
RotationAxis[1] = Random();
RotationAxis[2] = Random();
RotationAngle = 360.0f * Random();
RotationSpeed = 360.0f * Random();
Color[0] = color[0] + 0.2f * Random();
Color[1] = color[1] + 0.2f * Random();
Color[2] = color[2] + 0.2f * Random();
Age = 0;
}
void Update(float dt) // Apply one animation step
{
Position[0] += dt * Speed[0];
Position[1] += dt * Speed[1];
Position[2] += dt * Speed[2];
Speed[1] -= dt * 9.81f; // gravity
RotationAngle += dt * RotationSpeed;
Age += dt;
}
};
// Main
int main()
{
// Create main window
sf::RenderWindow app(sf::VideoMode(800, 600), "AntTweakBar simple example using SFML");
app.PreserveOpenGLStates(true);
// Particules
std::list<Particle> particles;
std::list<Particle>::iterator p;
float birthCount = 0;
float birthRate = 20; // number of particles generated per second
float maxAge = 3.0f; // particles life time
float speedDir[3] = {0, 1, 0}; // initial particles speed direction
float speedNorm = 7.0f; // initial particles speed amplitude
float size = 0.1f; // particles size
float color[3] = {0.8f, 0.6f, 0}; // particles color
float bgColor[3] = {0, 0.6f, 0.6f}; // background color
// Initialize AntTweakBar
TwInit(TW_OPENGL, NULL);
// Tell the window size to AntTweakBar
TwWindowSize(app.GetWidth(), app.GetHeight());
// Create a tweak bar
TwBar *bar = TwNewBar("Particles");
TwDefine(" GLOBAL help='This example shows how to integrate AntTweakBar with SFML and OpenGL.' "); // Message added to the help bar.
// Change bar position
int barPos[2] = {16, 240};
TwSetParam(bar, NULL, "position", TW_PARAM_INT32, 2, &barPos);
// Add 'birthRate' to 'bar': this is a modifiable variable of type TW_TYPE_FLOAT in range [0.1, 100]. Its shortcuts are [+] and [-].
TwAddVarRW(bar, "Birth rate", TW_TYPE_FLOAT, &birthRate, " min=0.1 max=100 step=0.1 keyIncr='+' keyDecr='-' ");
// Add 'speedNorm' to 'bar': this is a modifiable variable of type TW_TYPE_FLOAT in range [0.1, 10]. Its shortcuts are [s] and [S].
TwAddVarRW(bar, "Speed", TW_TYPE_FLOAT, &speedNorm, " min=0.1 max=10 step=0.1 keyIncr='s' keyDecr='S' ");
// Add 'speedDir' to 'bar': this is a modifiable variable of type TW_TYPE_DIR3F. Just displaying the arrow widget
TwAddVarRW(bar, "Direction", TW_TYPE_DIR3F, &speedDir, " opened=true showval=false ");
// Add 'color' to 'bar': this is a modifiable variable of type TW_TYPE_COLOR3F. Switched to HLS
TwAddVarRW(bar, "Color", TW_TYPE_COLOR3F, &color, " colorMode=hls opened=true ");
// Add 'bgColor' to 'bar': this is a modifiable variable of type TW_TYPE_COLOR3F. Switched to HLS
TwAddVarRW(bar, "Background color", TW_TYPE_COLOR3F, &bgColor, " colorMode=hls opened=true ");
// Initialize OpenGL states
glEnable(GL_DEPTH_TEST);
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
gluPerspective(90.f, (float)app.GetWidth()/app.GetHeight(), 0.1f, 100.f);
glMatrixMode(GL_MODELVIEW);
glEnable(GL_LIGHTING);
glEnable(GL_LIGHT0);
glEnable(GL_NORMALIZE);
glEnable(GL_COLOR_MATERIAL);
glColorMaterial(GL_FRONT_AND_BACK, GL_DIFFUSE);
// Init time
sf::Clock clock;
float time = clock.GetElapsedTime();
// Main loop
while (app.IsOpened())
{
// Process events
sf::Event event;
while (app.GetEvent(event))
{
// Send event to AntTweakBar
int handled = TwEventSFML(&event, 1, 6); // Assume SFML version 1.6 here
// If event has not been handled by AntTweakBar, process it
if( !handled )
{
// Close or Escape
if (event.Type == sf::Event::Closed
|| (event.Type == sf::Event::KeyPressed && event.Key.Code == sf::Key::Escape))
app.Close();
// Resize
if (event.Type == sf::Event::Resized)
{
glViewport(0, 0, event.Size.Width, event.Size.Height);
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
gluPerspective(90.f, (float)event.Size.Width/event.Size.Height, 1.f, 500.f);
glMatrixMode(GL_MODELVIEW);
// TwWindowSize has been called by TwEventSFML,
// so it is not necessary to call it again here.
}
}
}
if (!app.IsOpened())
continue;
// Update time
float dt = clock.GetElapsedTime() - time;
if (dt < 0) dt = 0;
time += dt;
// Update particles
p = particles.begin();
while (p != particles.end())
{
p->Update(dt);
if (p->Age >= maxAge)
p = particles.erase(p); // Die!
else
++p;
}
// Generate new particles
birthCount += dt * birthRate;
while (birthCount >= 1.0f)
{
particles.push_back(Particle(size, speedDir, speedNorm, color));
birthCount--;
}
// Clear depth buffer
glClearColor(bgColor[0], bgColor[1], bgColor[2], 1);
glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT);
// Draw particles
for (p = particles.begin(); p != particles.end(); ++p)
{
glColor4fv(p->Color);
glLoadIdentity();
glTranslatef(0.0f, -1.0f, -3.0f); // Camera position
glTranslatef(p->Position[0], p->Position[1], p->Position[2]);
glScalef(p->Size, p->Size, p->Size);
glRotatef(p->RotationAngle, p->RotationAxis[0], p->RotationAxis[1], p->RotationAxis[2]);
// Draw a cube
glBegin(GL_QUADS);
glNormal3f(0,0,-1); glVertex3f(0,0,0); glVertex3f(0,1,0); glVertex3f(1,1,0); glVertex3f(1,0,0); // front face
glNormal3f(0,0,+1); glVertex3f(0,0,1); glVertex3f(1,0,1); glVertex3f(1,1,1); glVertex3f(0,1,1); // back face
glNormal3f(-1,0,0); glVertex3f(0,0,0); glVertex3f(0,0,1); glVertex3f(0,1,1); glVertex3f(0,1,0); // left face
glNormal3f(+1,0,0); glVertex3f(1,0,0); glVertex3f(1,1,0); glVertex3f(1,1,1); glVertex3f(1,0,1); // right face
glNormal3f(0,-1,0); glVertex3f(0,0,0); glVertex3f(1,0,0); glVertex3f(1,0,1); glVertex3f(0,0,1); // bottom face
glNormal3f(0,+1,0); glVertex3f(0,1,0); glVertex3f(0,1,1); glVertex3f(1,1,1); glVertex3f(1,1,0); // top face
glEnd();
}
TwDraw();
// Finally, display the rendered frame on screen
app.Display();
}
// Un-initialize AntTweakBar
TwTerminate();
return EXIT_SUCCESS;
}